In 1978, 533 reels of nitrate film were thawed out from beneath a hockey rink in the Yukon Territory. Now we get to see what was on them.

Bill Morrison is a passionate archivist and a gifted collage artist, and sometimes — at his best — he is able to be both at once, using one area of expertise to deepen the other. In 2002’s brilliant “Decasia,” for example, he reassembled snippets of exposed and decaying nitrate film stock into a quasi-structuralist (and entirely non-narrative) meditation on death. Morrison recognizes that objects are endowed with their own unique histories, that raw material can be a medium unto itself, and his work invites viewers to think about cinema as a product of — and a witness to — its environment.

In that respect at least, “Dawson City: Frozen Time” is vintage Bill Morrison. Almost entirely comprised of archival footage and monochromatic stills, the film tells the story of its own existence and does so in exhaustive detail. Fortunately, it’s an incredible story to tell.

Only James Comey could be expected to remember every twist of fate or kink of fortune that made this movie possible, but the gist of it goes like this: In 1978, 533 reels of remarkably well-preserved film were thawed out from a sub-arctic swimming pool in a remote corner of the Yukon Territory called Dawson City, which lit up as part of the Klondike Gold Rush in the late 19th century and burned out just a few years later.

The reason you’ve never heard of Dawson City before is the same reason you’re hearing of it now: It’s way the hell out there, on the fringes of the map. So far as silent film distributors were concerned, it was literally the end of the line, and the owners of Dawson’s City cinema were told that it was cheaper to destroy the prints than to send them back. Most of them were ditched into the river. Some of them spontaneously burst into flames, destroying theaters and killing civilians. Others wound up underneath a hockey rink. Now, we get to see them.

Or someof them, anyway — some of some of them. Morrison has never had such a treasure trove of material before, and it’s understandable that he isn’t entirely sure what to do with this embarrassment of riches. He refers to the Dawson City Film Find as his “Titanic,” but it might be more appropriate to think of it as his Comstock Lode. It’s major, whatever you want to call it, and Morrison naturally wants to share as many of these artifacts with us as he can. Using (seemingly random) clips of the recovered nitrate as visual accompaniment for a text-driven tour of Dawson City that stretches from boom to bust and beyond, the filmmaker creates an illustrated requiem for a volatile moment in time when the frontiers of cinema overlapped with the frontiers of civilization.

This approach can feel exasperatingly random, especially as it begins to feel like Morrison is chronicling the rise and fall of Dawson City in real time, but the randomness of the surviving footage is also crucial to the film’s most evocative ideas. History is told by whatever happens to survive it. Watching this scattershot assembly of 100-year-old footage provides an evocatively impressionistic understanding of how we remember the past, how we rearrange the scraps left behind until they make some kind of sense. There’s gold in every detail, in every frame, in every inch of the map.

Dawson City might be a tiny town in the Yukon, but its story involves everyone from theater impresario Sid Grauman to — you guessed it — Frederick Trump (who made his fortune by operating the local brothel).

Still, while intermittently fascinating, “Frozen Time” too seldom reconciles Morrison’s zeal for preservation with his flair for creation. This is his most substantial work, but it’s also his driest. It’s clear that there’s a wonderstruck sense of awe lingering just beneath the surface, but Morrison can’t quite thread the needle between Ken Burns and Guy Maddin, between history and rediscovery (though it’s dryly amusing when the story of Dawson City touches upon the invention of the “Ken Burns Effect”). Morrison misses a crucial opportunity to add a more vibrant touch to the work, as he rushes through a prologue about how he found his way into the material, skirting over the footage he uncovered from the 1919 World Series and how that discovery might underscore the rest of his findings. The unrelenting dirge-like score from Sigur Rós collaborator Alex Somers only adds to the feeling that this film — this film of films — is still entombed in the past.

As an act of preservation, “Frozen Time” is a marvel, a miracle, a complete good. As an act of storytelling, it’s still a bit too cold for the nitrate to catch fire.